<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>暗黑模式🚀</title>
    <style>
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        html,
        body {
            width: 100%;
            height: 100%;
            background: #2376b7;
        }

        .container {
            width: 80px;
            height: 30px;
            display: flex;
        }
    </style>
</head>

<body>
    <div class="container">
        <span onclick="clickDarkly()">darkly</span>
    </div>
</body>
<script>
    function clickDarkly(){
        document.body.style.backgroundColor = "#1ba784";
    }
</script>

</html>